I read an interesting stat today that made me think about brain tumors logically - or at least mathematically.

I read that the overall incidence of primary brain tumors is around 4.7 in 100,000. Think about that. Those are incredibly low odds.

I then coupled that with the fact that in most U.S. states, headaches are the #1 reason for visits to the ER (A&E).

This tells me that many many people have headaches that are severe or concerning enough to convince them it's an emergency, but very few of those turn out to be brain tumors.